Nature's First Law 



gray, black and brown feathers, which have grad- 

 ually taken the place of the white ones, may be 



Seasonal plumages of ptarmigan 



From specimens in the American Museum of Natural History 

 a, summer, b, postnuptial or autumn, e, winter. 



scarcely distinguished from the soil and stones 

 among which the hen broods. 



RELIANCE ON DECEPTION 



Feeling absolute confidence in the harmonious 

 blending of their feathers with their natural sur- 

 roundings, many birds keep perfectly still even in 

 the actual presence of danger, thinking themselves 

 overlooked, as, indeed, they are apt to be. Another 



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